Sue
Ekk, an embryologist at the Institute for Reproductive Health in
Norwood, demonstrates the placing of a sperm in an egg, or the ICSI
procedure, that is used at the clinic in cases of male factor infertility.
(Craig Ruttle/The
Cincinnati Enquirer)

In 1997, Dr. Tucker was involved with the first U.S. birth from a frozen egg, which occurred in Atlanta.

Scientists have long been able to successfully thaw frozen sperm and, more recently, have reported success at thawing frozen human embryos. But success at freezing a woman's eggs has been rare.

The problem has been that tiny human eggs are still much larger and contain much more water than sperm cells or embryonic cells. As a result, there's more risk of crucial chromosome-laden fibers within the eggs being destroyed by frozen water crystals.

For years, scientists have hunted for ways around this problem by adjusting the pace of the freezing process and by using various chemicals to protect the egg structures during freezing. Now, some successes are being reported.

If freezing eggs proves successful, the entire fertility industry could change in several ways.

 The cottage industry of egg donation - an act of charity for some friends of infertile couples and a way of making money for some young women - could evolve into industrial-scale egg banking.

 Frozen eggs could simplify the issues that swirl around the fate of unused fertilized embryos and the decisions to abort some babies in multiple pregnancies.

 Egg freezing would offer new options to young women diagnosed with cancer.

In theory, even a teenager with leukemia who is nowhere near ready for parenthood could have some eggs frozen before starting radiation or chemotherapy treatments.

Some doctors, however, remain skeptical about the value of egg freezing for cancer patients. It may prove quicker and safer to remove and freeze an entire ovary rather than delay cancer treatments for several weeks while fertility drugs take effect to generate several eggs, Tucker said.

Regardless of the potential applications, much more study is needed before egg freezing becomes routine, says Dr. Pradeep Warikoo, a fertility expert at the Bethesda Center for Reproductive Health in Montgomery.

"Right now, the data isn't all that convincing," Warikoo says. "Some centers are trying to make a business out of oocyte banking, but what happens in 10 or 20 years when they try to thaw the eggs and find out there's a 10 percent survival rate?"